Abstract Title: *
Statistical analysis of the short-term variability of the recurrent nova RS Ophiuchi
Authors: *
Ts. B. Georgiev, S. Boeva, S. Ibryamov, G. Latev, J. Marti, G. Nikolov, B. Spassov, K.
Stoyanov, S. Tsvetkova, R. K. Zamanov
Institution: *
Institute of Astronomy and NAO
Preferred format: *
poster presentation
Abstract Text: *
We performed fractal analysis of the flickering variability of RS Oph. We analyze 29
monitorings, carried out simultaneously in B and V band in the period 2008-2017, with durations
1 – 3 hours. We scanned each time series by window with size T and traced out the behavior of
the structural parameter /Q/ and standard deviation /S/ as functions on T. The minimums of the
structural functions log Q = F (log T) shows basicly 2 kinds of structures. Their characteristic
sizes (quasi periods) are P = 25±10 min or P =75±15 min. The longest monitorings reveal also
structures with characteristic sizes ≈150 min. The linear parts of the deviation functions log S =
F(log T) show that the flickering is sometimes mono-fractal over ≈1 decimal magnitude of T, or
sometimes it is poly-fractal. The value SP of the deviation function at T = 0,5 P characterizes the
“power” of the flickering connected with this structure. It is typically 0.02 – 0.04 mag. The
respective fractal dimension DP is 1.4 -1.9. The values of SP and DP correlate with log T.
Generally, RS Oph poses more than one source of flickering. Sometimes one source
dominates. Sometimes two or even tree sources works together.